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- ID:
- ivo://CDS.VizieR/J/ApJ/719/1293
- Title:
- High precision orbits of 5 SB2 stars
- Short Name:
- J/ApJ/719/1293
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present high-precision radial velocities (RVs) of double-lined spectroscopic binary stars HD78418, HD123999, HD160922, HD200077, and HD210027. They were obtained based on the high-resolution echelle spectra collected with the Keck I/HIRES, Shane/CAT/Hamspec, and TNG/Sarge telescopes/spectrographs over the years 2003-2008 as part of the TATOOINE search for circumbinary planets. The RVs were computed using our novel iodine cell technique for double-line binary stars, which relies on tomographically disentangled spectra of the components of the binaries. The precision of the RVs is of the order of 1-10m/s, and to properly model such measurements one needs to account for the light-time effect within the binary's orbit, relativistic effects, and RV variations due to tidal distortions of the components of the binaries. With such proper modeling, our RVs combined with the archival visibility measurements from the Palomar Testbed Interferometer (PTI) allow us to derive very precise spectroscopic/astrometric orbital and physical parameters of the binaries.
- ID:
- ivo://CDS.VizieR/J/A+AS/135/503
- Title:
- Hipparcos southern B8-F2 stars radial velocities
- Short Name:
- J/A+AS/135/503
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Radial velocities have been determined for a sample of B8-F2 type stars observed by the Hipparcos satellite. Observations were obtained within the framework of an ESO key-program. Radial velocities have been measured using a cross-correlation method, the templates being a grid of synthetic spectra. The obtained precision depends on effective temperature and projected rotational velocity of the star as well as on a possible asymmetry of the correlation peak generally due to secondary components. New spectroscopic binaries have been detected from these a symmetries and the variability of the measured radial velocity. Simulations of binary and triple systems have been performed. For binaries our results have been compared with Hipparcos binary data. Adding the variable radial velocities, the minimum binary fraction has been found 60% for physical systems. Radial velocities have been determined for 581 B8-F2 stars, 159 being new. Taking into account published radial velocities, 39% south A-type stars with V magnitude lower than 7.5 have a radial velocity.
- ID:
- ivo://CDS.VizieR/J/AJ/152/213
- Title:
- Interferometry and spectroscopy of sigma Orionis
- Short Name:
- J/AJ/152/213
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present interferometric observations of the {sigma} Orionis triple system using the CHARA Array, NPOI, and VLTI. Using these measurements, we spatially resolve the orbit of the close spectroscopic binary (Aa,Ab) for the first time and present a revised orbit for the wide pair (A,B). Combining the visual orbits with previously published radial velocity measurements and new radial velocities measured at CTIO, we derive dynamical masses for the three massive stars in the system of M_Aa_=16.99+/-0.20M_{Sun}_, M_Ab_=12.81+/-0.18M_{Sun}_, and M_B_=11.5+/-1.2M_{Sun}_. The inner and outer orbits in the triple are not coplanar, with a relative inclination of 120{deg}-127{deg}. The orbital parallax provides a precise distance of 387.5+/-1.3pc to the system. This is a significant improvement over previous estimates of the distance to the young {sigma} Orionis cluster.
- ID:
- ivo://CDS.VizieR/J/A+A/393/965
- Title:
- Intrinsic frequencies of slowly pulsating B stars
- Short Name:
- J/A+A/393/965
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of detailed frequency analyses of a sample of thirteen confirmed slowly pulsating B stars. Our analysis is based on a combination of elaborate photometric and spectroscopic data-sets. The original sample consists of a mixture of five confirmed slowly pulsating B stars and twelve candidate slowly pulsating B stars discovered thanks to the photometric measurements of the HIPPARCOS satellite. HD 55522 and HD 131120 turn out to be chemically peculiar stars. HD 169978 and HD 69144 are two ellipsoidal variables for which no intrinsic variability is found. At least nine of the thirteen studied slowly pulsating B stars are multi-periodic. We here present the observed amplitudes, phases and their corresponding standard errors of the variations with the accepted intrinsic frequencies in the first three normalised velocity moments of the SiII 413.0nm line profiles, in the seven filters of the Geneva photometric system, and in the Hp filter of the HIPPARCOS photometric system. They are determined by fitting the data with a superposition of sinusoidal models with reference epoch HJD=2450000. For the higher order moments, the appropriate interaction terms are also taken into account (see Mathias et al., 1994A&A...283..813M). We use the same notations as in Aerts (1996A&A...314..115A) and Aerts (2000, Cat. <J/A+A/361/245>) for the amplitudes of respectively the velocity moments and the variations in the Geneva data.
- ID:
- ivo://CDS.VizieR/J/AJ/142/160
- Title:
- Kepler Mission. II. Eclipsing binaries in DR2
- Short Name:
- J/AJ/142/160
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Kepler Mission (launched in 2009 March) provides nearly continuous monitoring of ~156000 objects with unprecedented photometric precision. Coincident with the first data release, we presented a catalog of 1879 eclipsing binary systems identified within the 115deg^2^ Kepler field of view (FOV). Here, we provide an updated catalog from paper I (Prsa et al. 2011, Cat. J/AJ/141/83) augmented with the second Kepler data release which increases the baseline nearly fourfold to 125 days. Three hundred and eighty-six new systems have been added, ephemerides and principal parameters have been recomputed. We have removed 42 previously cataloged systems that are now clearly recognized as short-period pulsating variables and another 58 blended systems where we have determined that the Kepler target object is not itself the eclipsing binary. A number of interesting objects are identified. We present several exemplary cases: four eclipsing binaries that exhibit extra (tertiary) eclipse events; and eight systems that show clear eclipse timing variations indicative of the presence of additional bodies bound in the system. We have updated the period and galactic latitude distribution diagrams. With these changes, the total number of identified eclipsing binary systems in the Kepler FOV has increased to 2165, 1.4% of the Kepler target stars.
- ID:
- ivo://CDS.VizieR/J/A+A/648/A113
- Title:
- Kepler red giants in eclipsing binaries RVs
- Short Name:
- J/A+A/648/A113
- Date:
- 22 Feb 2022
- Publisher:
- CDS
- Description:
- Eclipsing binaries (EBs) are unique targets for measuring accurate stellar properties and constraining stellar evolution models. In particular, it is possible to measure masses and radii at the few percent level for both components of a double-lined spectroscopic EB (SB2-EB). On the one hand, detached EBs hosting at least one star with detectable solar-like oscillations constitute ideal test objects to verify the ability of ensemble asteroseismology to derive stellar properties. On the other hand, the oscillations and surface activity of stars that belong to EBs offer unique information about the evolution of binary systems. This paper builds upon previous works dedicated to red giant stars (RG) in EBs; so far 20 known systems have been discovered by the NASA Kepler mission. We report the discovery of 16 RGs in EBs, which are also from the Kepler data, leading to a total of 36 confirmed RG stars in EBs from the original Kepler mission. This new sample includes three SB2-EBs with oscillations, resulting in a total of 14 known SB2-EBs with an oscillating RG component. This sample also includes six close systems in which the RG display a clear surface activity and complete oscillation suppression. Based on dedicated high-resolution spectroscopic observations (Apache Point Observatory, Observatoire de Haute Provence), we focus on three main aspects. Firstly, from the extended sample of 14 SB2-EBs, we confirm that the simple application of the asteroseismic scaling relations to RGs overestimates masses and radii of RGs by about 15% and 5 %. This bias can be reduced by employing either new asteroseismic reference values for RGs or model-based corrections of the asteroseismic parameters. Secondly, we confirm that close binarity leads to a high level of photometric modulation (up to 10%) and a suppression of solar-like oscillations. In particular, we show that it reduces the lifetime of radial modes by a factor of up to 10. Thirdly, we use our 16 new systems to complement previous observational studies that aimed to constrain tidal dissipation in interacting binaries. We confirm the important role of the equilibrium tide in binary evolution, but we also identify systems with circular orbits despite relatively young ages, which suggests the need to explore complementary tidal dissipation mechanisms in the future. Finally, as a by-product, we report the measurements of mass, radius, and age of three M-dwarf companion stars.
- ID:
- ivo://CDS.VizieR/J/ApJ/697/1103
- Title:
- Kinematics of Orion Nebula Cluster
- Short Name:
- J/ApJ/697/1103
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a kinematic study of the Orion Nebula Cluster (ONC) based upon RVs measured by multifiber echelle spectroscopy at the 6.5m MMT and Magellan telescopes. Velocities are reported for 1613 stars, with multi-epoch data for 727 objects as part of our continuing effort to detect and analyze spectroscopic binaries (SBs). We confirm and extend the results of Furesz et al. (2008, Cat. J/ApJ/676/1109), showing that the ONC is not relaxed, consistent with its youth, and that the stars generally follow the position-velocity structure of the moderate density gas in the region, traced by ^13^CO. The additional RVs we have measured enable us to probe some discrepancies between stellar and gaseous structure which can be attributed to binary motion and the inclusion of nonmembers in our kinematic sample. Our multi-epoch data allow us to identify 89 SBs; more will be found as we continue monitoring. Our results reinforce the idea that the ONC is a cluster in formation, and thus provide a valuable testing ground for theory.
- ID:
- ivo://CDS.VizieR/J/MNRAS/357/497
- Title:
- Kinematics of W UMa-type binaries
- Short Name:
- J/MNRAS/357/497
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The kinematics of 129 W Ursae Majoris type binaries (W UMas) were studied. The sample is heterogeneous with different orbits and physically different components from F to K spectral-type main-sequence stars. The computed U, V, W space velocities indicate that the sample is also heterogeneous in velocity space.
- ID:
- ivo://CDS.VizieR/J/MNRAS/477/4641
- Title:
- LAMOST DR5 White dwarf-main sequence binaries
- Short Name:
- J/MNRAS/477/4641
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the data release (DR) 5 catalogue of white dwarf-main sequence (WDMS) binaries from the Large sky Area Multi-Object fibre Spectroscopic Telescope (LAMOST). The catalogue contains 876 WDMS binaries, of which 757 are additions to our previous LAMOST DR1 sample and 357 are systems that have not been published before. We also describe a LAMOST-dedicated survey that aims at obtaining spectra of photometrically selected WDMS binaries from the Sloan Digital Sky Survey (SDSS) that are expected to contain cool white dwarfs and/or early-type M dwarf companions. This is a population under-represented in previous SDSS WDMS binary catalogues. We determine the stellar parameters (white dwarf effective temperatures, surface gravities and masses, and M dwarf spectral types) of the LAMOST DR5 WDMS binaries and make use of the parameter distributions to analyse the properties of the sample. We find that, despite our efforts, systems containing cool white dwarfs remain under-represented. Moreover, we make use of LAMOST DR5 and SDSS DR14 (when available) spectra to measure the NaI {lambda}{lambda} 8183.27, 8194.81 absorption doublet and/or H{alpha} emission radial velocities of our systems. This allows identifying 128 binaries displaying significant radial velocity variations, 76 of which are new. Finally, we cross-match our catalogue with the Catalina Surveys and identify 57 systems displaying light-curve variations. These include 16 eclipsing systems, two of which are new, and nine binaries that are new eclipsing candidates. We calculate periodograms from the photometric data and measure (estimate) the orbital periods of 30 (15) WDMS binaries.
